Charles Townes, physicist who invented the laser, dies at 99

Charles Townes, physicist who invented the laser, dies at 99
Charles Townes, co-inventor of the laser and a Nobel Prize-winner in physics, speaks after winning the Templeton Prize in New York on March 9, 2005. (Gregory Bull / AP)

Charles Townes, the Columbia University physicist who transformed modern society with his invention of the maser and the laser, receiving the 1964 Nobel Prize in physics for his effort, has died. He was 99.

Townes, who had been in failing health, died Tuesday in Oakland while on his way to a hospital, according to UC Berkeley. He had been a professor of physics at the university since 1967.




Jan 28, 3:10 p.m.: An earlier version of this obituary stated that Charles Townes died in Berkeley. He died in Oakland. Also, it said that Townes and Mother Teresa were the only two people to win both the Nobel and the Templeton prizes. There have been a handful of others.


In 2005, Townes also won the Templeton Prize for Progress Toward Research or Discoveries about Spiritual Realities.

Few other modern inventions have had the wide-ranging impact of the laser throughout all areas of society. Lasers are at the core of the CD and DVD players in the home, the bar-code scanner in the supermarket, range-finders and altimeters used by the military, speed detectors used by state troopers and a host of other commercial products.

In medicine, their uses include laser scalpels, smoothing the skin, removing tattoos, reattaching retinas and shaping the cornea to eliminate the need for glasses. In astronomy, they are used for measuring distances and examining cosmological phenomena in deep space. In industry and government, they are used for high-speed transmission of data over fiber-optic cables.

Chemist Ahmed H. Zewail of Caltech, himself a Nobel laureate for his work using lasers to study chemical reactions, called Townes "one of the great physicists of the 20th century."

Physicist Theodor W. Hänsch of Germany's Max Planck Institute for Quantum Optics, upon learning that he would receive a Nobel of his own for using lasers to study the properties of atoms and molecules, said, "We all together stand on the shoulders of our giant, Charlie Townes."

The technology has become so common that the term laser, an acronym for "light amplification by the stimulated emission of radiation" coined by Townes and his students, has become generally understood throughout society — even though few understand the principles behind it.

Normal white light, like that emitted by the sun or a lightbulb, is a jumbled mixture of wavelengths, or colors — all out of step with one another, like a mass of people walking across a bridge. A laser, in contrast, emits a narrow beam of light of one defined wavelength in lockstep, like soldiers marching across that same bridge.

And while the footsteps of the crowd have little effect on the bridge, the combined footfalls of the soldiers have much greater impact, causing the bridge to shake and tremble. Similarly, the coherent light from a laser carries much more power than simple white light, allowing it to burn through flesh or even steel.

The idea of stimulated emission of radiation at the heart of the laser was put forth by Albert Einstein in 1917. He reasoned that the absorption of radiation of a particular wavelength by atoms will stimulate them to emit radiation of the same wavelength.

Physicists, however, viewed this primarily as a theoretical concept because atoms typically absorb more light than they emit, leading to a loss of energy rather than amplification.

Townes' essential contribution was to identify and create conditions in which large numbers of atoms were in an unstable high-energy state in which they would emit more energy than they absorbed.

He traced his seminal discovery of the maser to a "revelation" on a park bench in 1951.

He had been working for years to decrease the wavelength of microwaves to enhance their use in communications and headed a Navy committee charged with solving the problem.

Microwaves can have wavelengths as long as a few feet, but Townes was working with wavelengths of about half an inch and seeking still shorter ones, which would have more uses. But electronic devices that might generate such short wavelengths were too small to produce sufficient power for any foreseeable application.

On the morning of the last day of a futile meeting in Washington, D.C., to consider new approaches to the problem, Townes sat on a park bench and contemplated the issue. He reasoned that developing electronic amplifiers would not work and started to imagine using molecules, which produce radiation when they vibrate at high speeds.

The problem was that a lot of heat is normally required to make the molecules vibrate, and that heat destroys the molecules.

He speculated that a flash of bright light could be used to create a population of excited ammonia molecules and that confining them in an appropriate cavity would limit the wavelengths that they could then emit.

"So I took out a piece of paper and just scratched it out," he later said. Ultimately, he concluded, "Hey, this looks like it might work."

Excited, he returned to his hotel room and consulted with physicist Arthur Schawlow, a collaborator and friend who later became his brother-in-law.

"I told him about it and he said, 'OK, well, maybe.' And so that's how the idea started," Townes said. "It was like a sudden revelation."

He did not, however, share his thoughts with the Navy committee, but instead returned to Columbia and began working on the device.

His colleagues were skeptical. Niels Bohr, one of the great quantum physicists, and Nobel laureate Isadore Rabi, head of the university's physics department, told Townes his maser idea would never work and urged him to abandon the project.

Undaunted, he and Schawlow successfully completed the first device in 1954, dubbing it a maser for "microwave amplification by stimulated emission of radiation."

The pair used the same concepts to design a device that would emit light at frequencies one-100,000th as short as microwaves, publishing their design in the December 1958 issue of the journal Physical Review and obtaining a patent in 1959.

While their publication of the design for a maser had not stimulated much interest, others fell on this new idea avidly. In 1960, Theodore Maiman of the Hughes Research Institute in Malibu built the first working laser, largely based on their design, producing a sharp beam of ruby-red light.

Townes shared the Nobel prize in 1964 with Nicolay Gennadiyevich Basov and Aleksandr Mikhailovich Prokhorov of the Soviet Union, who also made significant contributions to the development of the maser and laser. (Schawlow was awarded the Nobel in physics in 1981 for his later work with laser spectroscopy.)

Since then, several more Nobels have been awarded for work that involved, refined or depended on lasers.

The invention of the laser was also claimed by the late Gordon Gould. As a Columbia University graduate student in the 1950s, he drew up a design for the laser on his own during a manic weekend in 1957. Gould had his own epiphany about how a laser should work and produced drawings and notes for the device.

Recognizing their potential, he had his lab notebook notarized at a local candy store. But he didn't file for a patent until 1959, after Townes and Schawlow had already submitted their application.

Gould spent nearly 30 years in court battles to have his own contributions to laser technology patented. He succeeded in 1988, ultimately collecting more than $30 million in royalties for his "candy store patent."


Charles Hard Townes was born on July 28, 1915, in Greenville, S.C. The family lived on a small farm, where Townes grew up milking cows, picking fruit and indulging his passion for collecting insects, especially butterflies.


He was tempted to try a career in entomology but felt he would be eclipsed in that field by his brother, the late Henry Keith Townes Jr., a founder of the American Entomological Institute.

He earned bachelor's degrees in modern languages and physics from Furman University in 1935, followed by a master's in physics from Duke University in 1936. He was drawn to physics for what he called its "beautifully logical structure."

A brilliant student, Townes moved to Caltech to complete his doctorate in 1939, studying with some of the great physicists of all time, including J. Robert Oppenheimer and Robert A. Millikan. Townes' thesis was on isotope separation and nuclear spins.

He graduated during the Great Depression, when academic jobs were scarce. Townes joined the technical staff at Bell Labs in New York, where he developed engineering skills and worked on the development of radar-based bombing systems during World War II.

Although at the time he was disappointed to go to an industry lab, Townes later said that his lengthy interlude as an engineer proved instrumental to his discoveries.

He moved to Columbia University in 1948, where he conducted his fundamental work on the maser and laser.

Townes took a leave of absence from Columbia from 1959 to 1961 to direct research for the nonprofit Institute for Defense Analyses in Washington. He then moved to the Massachusetts Institute of Technology in 1961 as professor of physics and provost. In 1967, he became a professor of physics at UC Berkeley, where he finished his career.

Townes' lifelong creativity continually pushed him in new directions.

In the 1940s it was radar, in the 1950s the maser and in the 1960s the laser. In the 1970s he began to make substantial contributions in astrophysics that relied partly on his earlier discoveries. Townes was an originator of a method to increase telescopic power by tying together light from two or more telescopes. Today the world's most powerful telescopes use the technique. In the latter part of his life, Townes turned his gaze to the sky in search for life beyond our world.

Caltech's Zewail attributed Townes' penchant for reinventing himself to his knowledge of engineering and other fields — well beyond the breadth many other physicists in this era of extreme specialization.

Townes was fluent in several languages. In his youth, he was an accomplished singer who in his spare time studied voice at the Juilliard School while working at Bell Labs.

"When you have a broad enough education, you can touch on different areas throughout your career without fear," Zewail said.

Fearlessness combined with Townes' deep skepticism of conventional wisdom—a quality that helped him overcome critics who initially dismissed his ideas.

A similar determination served Townes well as chairman of several influential government commissions, including the Apollo moon project's science panel and President Reagan's advisory commission on the MX nuclear-tipped missile.

Townes' accomplishments in science were always guided by strong religious feelings. He said he regarded his "revelation" on the park bench, when he conceived of the design for the maser, as a sign of the interplay between spiritual belief and scientific inquiry.

His landmark 1966 article in IBM's Think magazine, "The Convergence of Science and Religion," attempted to reconcile the sometimes-warring camps.

To Townes, science was the pursuit of understanding about the order of the universe, religion the pursuit of understanding and acceptance of the meaning of the universe.

"Science and religion are both universal, and basically very similar," he wrote. "The essential role of faith in religion is so well known that taking things on faith rather than proving them is usually taken as characteristic of religion, and as distinguishing religion from science. ... It is just this faith in an orderly universe, understandable to man, which allowed the basic change from an age of superstition to an age of science."

"The fact that the universe had a beginning is a very striking thing," Townes told The Times in 1996, in regard to the widely accepted Big Bang theory. "How do you explain that unique event" without God?

Upon receiving the $1.5-million Templeton Prize, he donated half the money to Furman and the rest to church-based charities.

Townes married the former Frances H. Brown in 1941. She survives him, along with their four daughters, Linda Rosenwein, Ellen Townes-Anderson, Carla Kessler and Holly Townes; six grandchildren and two great-grandchildren.

Piller and Maugh are former Times staff writers.